Tin.Man, 1084 is meant to be a forging steel, which is why more care isn't taken to make sure it is dead flat. I don't think you'll find any high carbon steel except O1 that is perfectly flat. Even then, Precision Ground O1 still has warps and bows in it. I've never seen any piece of steel from any supplier that comes perfectly flat. That's why one of the steps to making a knife is for the maker to flatten it himself. Even PG stainless will have twists, warps, and bows in it that must be taken out by the maker.